Data is everywhere

• Websites with APIs
• Websites without APIs
• City/Province/Country open data portals
• Any of the work you do.

Napolean’s Invasion of Russia

Charles Minard’s Map of Napolean’s Invasion of Russia

2 easy ways to plot data (you’ll never believe number 2!)

• We’re all a bunch of millennials. We won’t read anything that hasn’t been turned into a list with a click-baity title.
• I’ve got a dataset of our generation.

What the data looks like

• A CSV of 15 101 Buzzfeed listicles.
• With the columns: “title”, “listicle_size”, “num_fb_shares”, and “url”
• e.g.: “6 Reasons To Fall In Love With Maggie Stiefvaters Raven Cycle”,6,2276,“[truncated url]”
• Available here.

What we’ll need

• A copy of the R programming language (Your package manager should have this)
• The following packages (CRAN should have these):
  • ggplot2
  • RColorBrewer
  • scales

Grab those dependencies:

install.packages(c("ggplot2", "RColorBrewer", "scales"),
    repos='http://r.adu.org.za/')
library(ggplot2)
library(scales)
library(grid)
library(RColorBrewer)

Read in the data

R makes this very easy for us. Just a single line and we can work with the data.

df <- read.csv("buzzfeed_linkbait_headlines.csv", header=T)

That line turns the csv into a data frame - sort of like a table in R. You can even just put a hyperlink in there and R will download the file. header=T tells R that the first line is the header.

Always try to be answering a question

• It helps to ask a question and then try to answer it by plotting some data.
• Our questions:
• What is the average length of a listicle that Buzzfeed publishes?
• Does the length of a listicle affect how popular it is on social media?

What is the distribution of listicle lengths in that Buzzfeed publishes?

library(ggplot2)
library(scales)
library(grid)
library(RColorBrewer)
df <- read.csv("buzzfeed_linkbait_headlines.csv", header=T)
plot <- ggplot(df, aes(listicle_size)) + geom_histogram(binwidth=1)
plot

We pass in the dataframe to ggplot. We then specify the aesthetics, in this case listicle_size is a column in the dataframe (R knows that from the headings in the CSV) and ggplot works out that we want this on the x-axis.

Result

Let’s make that look a bit better

• That graph looked pretty good but we can do better.
• I’ve got a nice little function that acts like a theme for a ggplot graph. You can get it here.

library(ggplot2)
library(scales)
library(grid)
library(RColorBrewer)
source("fte-theme.R")
df <- read.csv("buzzfeed_linkbait_headlines.csv", header=T)
plot <- ggplot(df, aes(listicle_size))
    + geom_histogram(binwidth=1)
    + fte_theme()
plot

Result

We’re getting there

So that looked a bit better. But I think we can still add a bit more.

Let’s give it some axis titles, a nice heading, and fit a few more breaks along the x and y axes. We’ll also add a touch of color and transparency. I’ve omitted some of the imports for brevity.

df <- read.csv("buzzfeed_linkbait_headlines.csv", header=T)
plot <- ggplot(df, aes(listicle_size))
    + geom_histogram(binwidth=1, fill="#c0392b", alpha=0.75)
    + fte_theme()
    + labs(title="Distribution of Listicle Sizes for BuzzFeed Listicles",
    x="# of Entries in Listicle",
    y="# of Listicles")
    + scale_x_continuous(breaks=seq(0,50, by=5))
    + scale_y_continuous(labels=comma)
    + geom_hline(yintercept=0, size=0.4, color="black")
plot

Result

Are longer listicles more popular on social media?

The amazing ggplot2 can also do scatter plots. We can give it all 15 101 points to plot and it’ll happily do that for us. Try that in excel.

df <- read.csv("buzzfeed_linkbait_headlines.csv", header=T)
plot <- ggplot(df, aes(x=listicle_size, y=num_fb_shares)) +
      geom_point()
plot

Result

That looks a bit iffy

You may be able to understand that graph but it has one big issue. There are a few listicles in the dataset with over 1 000 000 shares and that forces the rest of the points really close to the bottom. But we can fix this. With a log scale!

df <- read.csv("buzzfeed_linkbait_headlines.csv", header=T)
plot <- ggplot(df, aes(x=listicle_size, y=num_fb_shares)) +
      geom_point(alpha=0.05) +
      scale_y_log10(labels=comma)
plot

Also note that I’ve given each point an alpha value of 0.05. This means that each point is only 5% opaque (or 95% transparent). This serves to enhance places in the plot where many points are congregated.

Result

But can it look better?

Of course! Add our theme again and some axis titles.

df <- read.csv("buzzfeed_linkbait_headlines.csv", header=T)
plot <- ggplot(df, aes(x=listicle_size, y=num_fb_shares)) +
    geom_point(alpha=0.05) +
    scale_y_log10(labels=comma) +
    fte_theme() +
    labs(x="# of Entries in Listicle",
    y="# of Facebook Shares",
    title="FB Shares vs. Listicle Size for BuzzFeed Listicles")
plot

Result

Let’s add a few final touches

df <- read.csv("buzzfeed_linkbait_headlines.csv", header=T)
plot <- ggplot(df, aes(x=listicle_size, y=num_fb_shares)) +
    geom_point(alpha=0.05, color="#c0392b") +
    scale_x_continuous(breaks=seq(0,50, by=5)) +
    scale_y_log10(labels=comma, breaks=10^(0:6)) +
    scale_y_log10(labels=comma) +
    geom_hline(yintercept=1, size=0.4, color="black") +
    geom_smooth(alpha=0.25, color="black", fill="black") +
    fte_theme() +
    labs(x="# of Entries in Listicle",
    y="# of Facebook Shares",
    title="FB Shares vs. Listicle Size for BuzzFeed Listicles")
plot

We’ve also added a line of best fit (with confidence).

Result